1. Field of the Invention
This invention relates to a light emitting device sealed a light emitting element with translucent sealing material.
2. Background Information
There has been a variety of proposals for light emitting devices in which lighting source is a light emitting element. For instance, a light emitting device in which a glass material covers a light emitting element and close thereto (see JP-2000-299503-A).
However, the glass sealed body formed by hydrolytic polymerization by sol-gel method is formed much thicker than the thickness of a light emitting element, and it is therefore believed to be susceptible to cracking due to shrinkage in the course of molding, and such glass film has extremely poor gas barrier performance.
When a light emitting device is to be used in a harsh environment, it is common for the plastic material that is used to be one with excellent resistance to heat and weathering. However, plastic materials with excellent resistance to heat and weathering tend to have low gas barrier performance.
In particular, when the mounting component of a light emitting device designed for automotive use is made from a metal reflecting member, the mounting component undergoes sulfide blackening under the effects of high temperature and humidity in the atmosphere and the heat generated by the light emitting element, and this can markedly lower the output of the light emitting device.